Configuration Tasks

This section describes how to configure the 2-Port, 4-Port, and 8-Port Clear-Channel T3/E3 Serial SPAs for the Cisco ASR 1000 Series Routers and verify the configuration. For information about managing your system images and configuration files, refer to the following:

Required Configuration Tasks

This section lists the required configuration steps to configure the 2-Port and 4-Port T3/E3 Serial SPA. Some of the required configuration commands implement default values that might be appropriate for your network. If the default value is correct for your network, then you do not need to configure the command.

Setting the Card Type

The SPA is not functional until the card type is set. Information about the SPA is not indicated in the output of any show commands until the card type has been set. There is no default card type.

Note

The card type command is not required to set the serial mode for the 8-Port Clear-Channel T3/E3 SPA. Therefore, this command is not supported in the 8-Port Clear-Channel T3/E3 SPA. This SPA supports both T3 and E3 configurations at the port level, which can be changed without reloading the SPA. The framing type that is configured determines whether a port is in the T3 mode or E3 mode. During first time initialization, by default, all the ports of the 8-Port Clear Channel T3/E3 SPA come up in the T3 mode and C-bit framing. For subsequent reloads, the ports come up in the modes they were configured and saved in. For more information on mixed interface types, see the Configuring Framing.

To set the card type for the 2-Port and 4-Port T3/E3 Clear-Channel Serial SPAs, complete these steps:

SUMMARY STEPS

1.
Router# configureterminal

2.
Router(config)# cardtype{t3|e3}slot subslot

3.
Router(config)# exit

DETAILED STEPS

Command or Action

Purpose

Step 1

Router# configureterminal

Enters global configuration mode.

Step 2

Router(config)# cardtype{t3|e3}slot subslot

Sets the serial mode for the SPA:

t3—Specifies T3 connectivity of 44210 kbps through the network, using B3ZS coding.

e3—Specifies a wide-area digital transmission scheme used predominantly in Europe that carries data at a rate of 34010 kbps.

Specifying the Interface Address on a SPA

SPA interface ports begin numbering with “0” from left to right. Single-port SPAs use only the port number 0. To configure or monitor SPA interfaces, you need to specify the physical location of the SIP, SPA, and interface in the CLI. The interface address format is slot/subslot/port, where:

slot—Specifies the chassis slot number in the Cisco ASR 1000 Series Aggregation Services Routers where the SIP is installed.

subslot—Specifies the slot of the SIP where the SPA is installed.

port—Specifies the number of the individual interface port on a SPA.

The following example shows how to specify the first interface (0) on a SPA installed in the first subslot of a SIP (0) installed in chassis slot 2:

Router(config)# interface serial 2/0/0

This command shows a serial SPA as a representative example, however the sameslot/subslot/port format is similarly used for other SPAs (such as ATM and POS) and other non-channelized SPAs.

eic string—Specifies the Equipment Identification Code (up to 10 characters), which is a value used to describe a specific piece of equipment according to ANSI T1.107-1995.

fic string—Specifies the Frame Identification Code (up to 10 characters), which is a value used to identify where the equipment is located within a building at a given location according to ANSI T1.107-1995.

generator string—Specifies the Generator number string sent in the MDL Test Signal message; can be up to 38 characters.

lic string—Specifies the Location Identification Code (up to 11 characters), which is a value used to describe a specific location according to ANSI T1.107-1995.

pfi string—Specifies the Path Facility Identification Code sent in the MDL Path message; can be up to 38 characters.

port string—Specifies the port number string sent in the MDL Idle Signal message; can be up to 38 characters.

unit string—Specifies the Unit Identification Code (up to 6 characters), which is a value that identifies the equipment location within a subslot according to ANSI T1.107-1995.

transmit idle-signal—Enables transmission of the MDL Idle-Signal message. An MDL Idle-Signal message, as defined by ANSI T1.107, is distinguished from path and test signal messages in that it contains a port number as its final data element.

transmit path—Enables transmission of the MDL Path message. An MDL Path message, as defined by ANSI T1.107, is distinguished from idle and test signal messages in that it contains a facility identification code as its final data element.

transmit test-signal—Enables transmission of the MDL Test-Signal message. An MDL Test-Signal message, as defined by ANSI T1.107, is distinguished from path and idle signal messages in that it contains a generator number as its final data element.

Configuring Scramble

T3/E3 scrambling is used to assist clock recovery on the receiving end. Scrambling is designed to randomize the pattern of 1s and 0s carried in the physical layer frame. Randomizing the digital bits can prevent continuous, nonvariable bit patterns—in other words, long strings of all 1s or all 0s. Several physical layer protocols rely on transitions between 1s and 0s to maintain clocking.

Scrambling can prevent some bit patterns from being mistakenly interpreted as alarms by switches placed between the Data Service Units (DSUs).

To configure scrambling, use the following commands:

Command

Purpose

Router# configureterminal

Enters global configuration mode.

Router(config)# interfaceserialslot/subslot/port

Selects the interface to configure and enters interface configuration mode.

hdlc—High-Level
Data Link Control (HDLC) protocol for serial interface. This encapsulation
method provides the synchronous framing and error detection functions of HDLC
without windowing or retransmission. This is the default for synchronous serial
interfaces.

Configuring Cable Length

The cablelength command compensates for the loss in decibels based on the distance from the device to the first repeater in the circuit. A longer distance from the device to the repeater requires that the signal strength on the circuit be boosted to compensate for loss over that distance. To configure cable length, use the following commands:

Command

Purpose

Router# configureterminal

Enters global configuration mode.

Router(config)# interfaceserialslot/subslot/port

Selects the interface to configure and enters interface configuration mode.

Configuring Invert Data

Delays between the terminal equipment (TE) clock and data transmission indicate that the transmit clock signal might not be appropriate for the interface rate and length of cable being used. Different ends of the wire may have variances that differ slightly. Invert the clock signal to compensate for these factors. To configure invert data, use the following commands:

Command

Purpose

Router# configureterminal

Enters global configuration mode.

Router(config)# interfaceserialslot/subslot/port

Selects the interface to configure and enters interface configuration mode.

Configuring QoS Features on Serial SPAs

The SIPs and SPAs support many QoS features using modular QoS CLI (MQC) configuration. Since there are no serial SPA-specific QoS features, refer to your network processor documentation for QoS configuration information.

Saving the Configuration

To save your running configuration to nonvolatile random-access memory
(NVRAM), use the following command in privileged EXEC configuration mode:

Verifying the Interface Configuration

Besides using the showrunning-configuration command to display the configuration settings of your Cisco ASR 1000 Series Routers, use the showinterfacesserialcommand and the showcontrollersserialcommand to get detailed information on a per-port basis for your 2-Port and 4-Port T3/E3 Serial SPA.